Agricultural vehicles, such as tractors or agricultural draft vehicles, which have a PTO transmission or a PTO for driving mounted or towed working equipment are conventionally equipped with PTO brakes which are intended to prevent unintentional rotation of the PTO, for example by the PTO drive itself or by the working equipment. For example, when the vehicle is stationary with the engine running and a PTO speed pre-selected, the PTO is switched off, or put into a non-driven condition. At the same time, the PTO brake is activated. When the PTO is switched on again, the PTO brake is disconnected or deactivated.
Conventionally, a PTO speed is pre-selected. Although it is possible to set a neutral position for the PTO or to put the PTO speed to “neutral”, it is often the case that a operator forgets to do this, and so the PTO brake is activated when the operator leaves the driver's cab of the vehicle while the engine is running, for example to hook up working equipment and connect it to the PTO. In this case, it is not usually possible to insert the PTO when the working equipment is hooked up, because the PTO or a PTO journal cannot be manually rotated in order to put it in a suitable insertion position with the PTO brake activated. To insert the PTO, the operator must first switch the PTO speed to “neutral” again, inside the vehicle, so that the PTO is deactivated. This can be awkward and unproductive, because the devices mounted are becoming heavier and heavier, and because this disrupts and interrupts hooking up operation.